Tubing anchor



Oct. 16, 1962 c. c. DOUGLASS ETAL 3,058,526

TUBING ANCHOR Filed April 7, 1960 2 Sheets-Sheet 1 CHARLES C. DOUGLASSBQ OBERT T. E VANS INVEN TORS.

Oct. 16, 1962 c. c. DOUGLASS ET AL 3,058,526

TUBING ANCHOR Filed April 7, 1960 IN V EN TORS.

United rates 3,058,526 TUBING ANCHOR Charles C. Douglass, Tioga, N.Dak., and Robert T.

Evans, Duncan, Okla, assignors to Halliburton Company, a corporation ofDelaware Filed Apr. 7, 1960, Ser. No. 20,589 3 Claims. (Cl. 166216) Thisinvention relates to tubing anchors for use in oil wells, and moreparticularly to an arrangement for holding and removing tubing in a wellif, by accident, it has parted at some point above its lower end.

It is common practice to use steel tubing in oil Wells. Sometimes, dueto excessive strain, or due to corrosion,

or other factors, the tubing comes apart at some point in the well. Thelower portion of the tubing then falls and is damaged, and an expensivefishing job is then necessary to remove it.

For preventing the falling of parted tubing, catchers,

per se, are old in the art. However, ordinary catchers are not suitablefor use with slips or other latch-down devices which hold the lower endof the tubing against upward movement during normal operation.

It is an object of the present invention to provide an anchor for tubingused in a well which is capable of latching or fastening down its lowerend, and at the same time prevent the tubing from falling, in case itparts. An arrangement is provided for rendering the latch-down mechanisminactive, should a fishing job be required, so that the parted tubingcan readily be retrieved.

Other objects will be apparent from the following description of apreferred embodiment of the invention, when taken in connection with theaccompanying drawings, in which:

FIGURE 1 is a view in vertical cross section of a portion of an oil wellwith a tubing anchor constructed in accordance with the inventionlocated therein, the parts being shown in the relative positions theyoccupy while tubing is being lowered into the well;

FIGURE 2 is a vertical quarter section of the anchor which they occupywhen a fishing operation is being conducted to remove the parted tubingfrom the well; and FIGURE 5 is an elevational view of the J-slot shownin section in FIGURES 1-4.

Referring to the drawing in detail, it will be seen that FIGURE 1 showsa casing 10 cemented in a well bore.

On the lower end of tubing 11, there is an anchor consisting essentiallyof a mandrel 12, which is connected to the lower end of the tubing 11 bya threaded coupling 13, and an outer sleeve 14 threaded upon the mandrel12 by right-hand acme threads 15.

At its lower end, the mandrel 12 is provided with a tapered conicalwedge or spreader block 16; and at the lower end of the sleeve 14, thereis a cooperating tapered conical wedge or spreader block 17.

Coacting with the spreader blocks are conventional slips 13 which havetapered inner surfaces corresponding to those of the spreader blocks.

It will be seen that the spreader blocks 16 and 17 are so disposed as toface each other, so that either block can force the coasting slips 18outwardly, the block 16 acting on the slips 18 when the tubing 11 israised in the "ice casing 10 and the block 17 acting on the slips 18when the tubing 11 is lowered in the casing 10.

It will be observed that the lower end of the sleeve 14 abuts against ashoulder 19 on the mandrel 12. Thus the blocks on sleeve 14 and mandrel12 cannot be brought any closer together than shown in FIGURE 1. Howeverby rotation of mandrel 12 to the right (as viewed from above) thespreader blocks 16 and 17 may be separated further, if the sleeve 14 isheld against rotation.

The slips 18 are held in position between the spreader blocks 16 and 17by a suitable cage 20 and drag springs 21.

The cage 20 consists merely of an outer cylinder provided with windowsin which the slips 18 are yieldably held by leaf springs 22.

The cage 20 is provided with conventional pins 23 extending intoconventional J-slots 24 on the sleeve 14, so that there can be onlylimited relative longitudinal movement between the cage 20 and thesleeve 14 when the parts are in the running-in position shown inFIGURE 1. As shown in FIGURES l and 5, each J-slot 24 includes a firstgenerally elongate slot portion 24a extending axially of the anchor, asecond elongate portion 24b also extending axially of the anchor, and atransversely extending portion 24c connecting the intermediate part ofportion 241'; with portion 24a of the slot. In the running-in position,pins 23 are positioned in slot portions 24a which are of limited axialextent so as to restrict axial movement of the cage 20 to therebyprevent coaction between the spreader blocks and slips.

As long as the J-slot coupling is limiting relative longitudinalmovement between the cage 20 and the sleeve 14, neither of the spreaderblocks can force the slips 18 out wardly. When the tubing has beenlowered to the desired point in the well at which it is desired that thelower end be anchored, the tubing is rotated to the left sufliciently tobring the pins 23 into the longer portions 24b of the J-slots 24. Thisis possible because of the shoulder 19 on the mandrel 12. The sleeve 14cannot move down wardly on the mandrel 12 upon left-hand rotation of themandrel due to this shoulder. Hence the left hand torque on the mandrel12 is transmitted to the sleeve 14 to operate the J-slot connector.

There is then a situation where either of the blocks can set the slips'18 in the casing 10, the slips being held against falling by the dragsprings 21 and the cage 20 while the tubing 11, mandrel 12 and sleeve 14can be moved up or down with respect to the slips 18.

To place the parts of the anchor in the operating position shown inFIGURE 2, all that is necessary, therefore, is to turn the tubingslightly to the left and raise it.

When the spreader block 16 causes the slips 13 to grasp the casing,tension can be taken in the tubing. This is desired, for example, whenthe tubing is provided with a pump, and it is desired to avoid breathingor buckling of the tubing with each pump stroke.

Should the tubing come part, as illustrated in FIGURE 3, the slips 18are held against downward movement by the drag springs 21 and cage 20until the tubing falls far enough for the spreader block 17 to causethem to again grip the casing.

To remove the parted tubing from the Well, a fishing device, such as isillustrated at 25 is connected to the parted tubing. An attempt wouldthen be made to rotate the tubing to the right and cause the pins 23 tore-enter the horizontal portions of the J-slot 24. If this can bebrought about, the parted tubing can be fished out.

However, it may not be possible to effect the proper actions of the pins23 and J-slots 24-. In that event, continued right-hand rotation of thetubing will cause the spreader blocks 16 and 17 to separate to such adistance that the anchor can still be moved upwardly in the well.

3 This is brought about by the action of the acme thread between thesleeve 14 and the mandrel 12.

During the right-hand rotation, the cage will be held against rotationeither by the slips 18 or by the drag springs 21. The cage 20, throughthe pins 23 and slots 24, will hold the sleeve 14 against rotation. Themandrel 12 is free to rotate in the sleeve 14 in a right-hand directionhowever, and since it is connected to the tubing 11, this action can bebrought about. The result is that the parted tubing and the anchor canbe removed from the well regardless of the fact that the J-slotconnector cannot be manipulated.

While only one embodiment of the invention has been shown and described,it is obvious that various changes may be made without departing fromthe spirit of the invention, or the scope of the annexed claims.

What is claimed is:

I. An anchor for tubing in an oil well or the like comprising a mandreland sleeve assembly including a mandrel adapted to be connected to thetubing and a sleeve screw-threaded on the mandrel and upwardly movablethereon; an upwardly directed spreader block carried by said mandrel; adownwardly directed spreader block carried by said sleeve above saidupwardly directed spreader block; slips for engaging casing in the Wellpositioned between said spreader blocks and having upper surface meansadapted to coact with said sleeve carried spreader block and lowersurface means adapted to coact with said mandrel carried spreaderblocks, a cage encircling said mandrel and sleeve assembly for holdingsaid slips, said cage being slidably mounted on said assembly; dragsprings projecting from the exterior of said cage to engage .a wellwall; a J-slot on the exterior of said sleeve, said J-slot having afirst slot portion extending axially of said anchor, a second elongateportion extending axially of said anchor, and a transversely extendingportionconneoting an intermediate part of said second portion and saidfirst portion; and a pin extending from said cage into said J-slot, saidpin, when in said first slot portion limiting axial cage movement toprevent said coaction between said spreader blocks and said slips, andwhen moved through said transversely extending slot portion into saidsecond elongate slot portion, permitting said coaction.

2. An anchor as defined in claim 1 in which said sleeve is mounted, onsaid mandrel by a right hand threaded connection and in which saidmandrel is provided with a shoulder beneath the lower end of said sleevesuch that, with said sleeve engaging said shoulder, and said pin in saidfirst axially extending slot portion and opposite said transverselyextending slot portion, a left hand torque applied to said mandrel tomove said pin through said transversely extending slot portion into saidsecond elongate slot portion will not eflfect movement of said sleeve onsaid mandrel.

3. An anchor for tubing in an oil well or the like comprising a mandreland sleeve means assembly including a mandrel adapted to be connected tothe tubing and sleeve means mounted on the mandrel and upwardly movablethereon; an upwardly directed spreader block carried by said mandrel; adownwardly directed spreader block carried by said sleeve means abovesaid upwardly directed spreader block; slips for engaging casing in thewell positioned between said spreader blocks and having upper surfacemeans adapted to coact with said sleeve means carried spreader block andlower surface means adapted to coact with said mandrel carried spreaderblocks, cage means encircling said mandrel and sleeve means assembly forholding said slips, said cage means being slidably mounted on'saidassembly; drag springs projecting from the exterior of said sleeve meansto engage a well Wall; a J-slot connection between said cage means andsaid sleeve means, said connection including a J-slot on one of saidmeans, said J-slot having a first slot portion extending axially of saidanchor, a second elongate portion extending axially of said anchor, anda transversely extending portion connecting an intermediate part of saidsecond portion and said first portion; and a pin extending from theother of said means into said J-slot, said pin, when in said first slotportion limiting axial cage means movement to prevent said coactionbetween said spreader blocks and said slips, and when moved through saidtransversely extending slot portion into said second elongate slotportion, permitting said coaction.

References Cited in the file of this patent UNITED STATES PATENTS1,393,091 Mack May 6, 1919 1,653,547 Cameron Dec. 20, 1927 2,178,999Scott Nov. 7, 1939 2,247,188 Davis June 24, 1941 2,331,532 BassingerOct. 12, 1943 2,589,506 Morrisett Mar. 18, 1952 2,633,201 Clark Mar. 31,1953

